GENERALIZATIONS CONCERNING EARTHQUAKES 39 



the minor faults within its hmits or at its doors. 

 There is no recorded reason for suspecting damage 

 from them. It has also been stated that only hori- 

 zontal movements are destructive. If this statement 

 be true, then it is a reaffirmation of the fact that the 

 San Andreas line is the chief one about which to be 

 concerned. 



RELATIONS OF EARTH MOVEMENTS TO THE 

 ABYSSAL ESCARPMENT 



Although the ultimate seat of earth movement is 

 known to be far below the ground and we have treated 

 the San Andreas Rift as the site of the greatest surface 

 manifestations, the great Abyssal scarp which consti- 

 tutes the outer edge of the Continental Shelf (see 

 Plate I) may be looked upon with suspicion as a 

 site of probable faulting and other dangerous move- 

 ments. For this reason the great seismisms have 

 largely been phenomena of submarine faults near the 

 sea shores. Kingston, Santiago, Lisbon, San Francisco 

 and other places have been examples. There are not- 

 able exceptions of course. 



There are many logical reasons why this should 

 be. The oscillations of tides, the depositions of mar- 

 ginal sediments are disturbing adjustments of load. 



Los Angeles, instead of being situated near or upon 

 the immediate edge of the Abyssal scarp, is over 

 one hundred miles away from it, twice as far from 

 it as is San Francisco. 

 TESTIMONY OF THE INGLEWOOD FAULT LINE 



The one possible fault line of the Los Angeles vic- 

 inity upon which suspicion might be cast is the Ingle- 

 wood fault line. This is associated with the Domin- 



